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Towards High-Efficiency Buildings for Sustainable Energy Transition: Standardized Prefabricated Solutions for Roof Retrofitting
Get PDFEnhancing energy efficiency in buildings plays a pivotal role in realizing the ambitious objective of achieving carbon neutrality by 2050, as outlined in the European Green Deal. Roofs represent the technical element most affected by energy phenomena related to heat transfer: in winter, roofing can lose up to 35% of heat, and the summer heat flux can even be higher. This paper provides a catalogue of optimized and sustainable solutions, with a specific focus on standardization and prefabrication principles, for enhancing the energy efficiency of the most prevalent types of roofs that characterize the national residential building heritage. The methodological approach that guided the research presented in this article was based on the identification and study of the most common roofings in the diverse national residential building heritage, followed by their classification according to their construction era. In the context of essential energy retrofitting of deteriorated residential building stock, 21 optimized standardized solutions have been identified. The outcome of performance evaluations of the proposed solutions allowed the implementation of a matrix that can be a valuable support for designers in selecting the most efficient precalculated and prefabricated solutions for the national residential building heritage based on energy performance and sustainability criteria
Hermite, Higher order Hermite, Laguerre type polynomials and Burgers like equations
Get PDFThe multivariable version of ordinary and generalized Hermite polynomials are the natural solutions of the classical heat equation and of its higher order versions. We derive the associated Burgers equations and show that analogous non-linear partial differential equations can be derived for Laguerre polynomials. The starting point of this extension is the Laguerre diffusive equation, whose nonlinear extension reveals interesting implications involving families of mixed polynomials. In this way we have a general scheme to obtain new exact explicit solutions for nonlinear PDEs by using Laguerre, Hermite and other families of polynomials of Appèl and non-Appèl type
Symmetries of the Electromagnetic Turbulence in a Tokamak Edge
Get PDFWe construct the low-frequency formulation of the turbulence characterizing the plasma in a Tokamak edge. Under rather natural assumptions, we demonstrate that, even in the presence of poloidal magnetic fluctuations, it is possible to deal with a reduced model for turbulence dynamics. This model relies on a single equation for the electric potential from which all the physical turbulent properties can be calculated. The main result of the present analysis concerns the existence of a specific Fourier branch for the dynamics which demonstrate the attractive character of the two-dimensional turbulence with respect to non-axisymmetric fluctuations. The peculiar nature of this instability, affecting the non-axially symmetric modes, is discussed in some detail by recovering two different physical regimes
Sviluppo, produzione e caratterizzazione di compositi multistrato in rCF-PA6
Get PDFIl presente Rapporto Tecnico riassume le attività di R&S finalizzate alla produzione di compositi laminati realizzati mediante stampaggio per compressione a caldo di multistrato di tessuti (anche detti organosheets). Le attività sono state svolte all’interno del progetto EcoCarbonio “Circular Economy for the Carbon Fiber Industry”, (POR FESR 2014-2020, ID_1170458), finanziato con il Bando “Call Hub Ricerca e Innovazione” per Progetti Strategici di Ricerca, Sviluppo e Innovazione. Più nello specifico, i tessuti unidirezionali sono realizzati impiegando dei filati ibridi in fibra di carbonio da riciclo (rCF) e poliammide 6 (nylon 6) sviluppati e prodotti presso i laboratori di materiali compositi del Centro di Ricerche ENEA di Brindisi con lo scopo valorizzare un materiale di scarto (la fibra di carbonio presente in materiali compositi a fine vita o proveniente da scarti di lavorazione) che in questo modo diventa una materia prima seconda per la realizzazione di nuovi prodotti. I tessuti unidirezionali realizzati con i filati ibridi sviluppati sono quindi sovrapposti a realizzare un semilavorato multistrato che successivamente è compresso in una pressa a caldo, raggiungendo temperature che consentono la fusione del polimero termoplastico (PA6) che in tal modo funge da collante per le fibre di carbonio e conferisce stabilità strutturale e consistenza al componente (thermobonding). Le attività svolte sono state orientate alla determinazione dei parametri di processo che consentono di ottimizzare il composito laminato finale, in termini di geometria, spessore, planarità della superficie e in particolare prestazioni meccaniche. I prodotti ottenuti sono stati sottoposti ad un’intensa campagna di caratterizzazione, che include test meccanici e termici, microscopia elettronica a scansione e analisi micro-tomografica, al fine di individuare i potenziali campi di applicazione. Infine, è stata verificata la possibilità di riciclo degli organo-sheets così realizzati, una volta raggiunto lo status di fine vita, attraverso comminuzione dei materiali e successivo stampaggio per compressione che ha consentito la realizzazione di compositi ben strutturati e compatti. La successiva caratterizzazione ha tuttavia messo in evidenzia una significativa riduzione delle proprietà meccaniche dei prodotti riciclati, come era lecito attendersi data la diversa architettura del materiale.This Technical Report summarizes the R&D activities aimed at the production of laminated composites made by hot compression molding of multilayer fabrics (also referred to as organo-sheets). The activities were carried out within the EcoCarbonio project “Circular Economy for the Carbon Fiber Industry”, (POR FESR 2014-2020, ID_1170458), financed by the “Call Hub Ricerca e Innovazione” for Strategic Research, Development and Innovation Projects. More specifically, the unidirectional fabrics are manufactured using recycled carbon fiber (rCF) and polyamide 6 (nylon 6) based hybrid yarns, developed and produced at the composite materials laboratories of the ENEA Research Centre in Brindisi with the aim of valorising a waste material (the carbon fibers in end-of-life composite materials or coming from processing waste) which in this way becomes a secondary raw material for the creation of new products. The unidirectional fabrics made with the developed hybrid yarns are then superimposed to create a multilayer semi-finished product that is subsequently compressed in a hot press, reaching temperatures that allow the melting of the thermoplastic polymer (PA6) that in this way acts as a glue for the carbon fibers and gives structural stability and consistency to the component (thermobonding). The activities carried out were oriented to the determination of the process parameters that allow to optimize the final laminated composite, in terms of geometry, thickness, surface planarity and in particular mechanical performance. The products obtained were subjected to an intense characterization campaign, which includes mechanical and thermal tests, scanning electron microscopy and micro-tomographic analysis, in order to identify the potential fields of application. Finally, the possibility of recycling the organo-sheets thus produced, once they have reached the end-of-life status, was verified through comminution of the materials and subsequent compression molding that allowed the creation of well-structured and compact composites. However, subsequent characterization highlighted a significant reduction in the mechanical properties of the recycled products, as expected given the different architecture of the material
Wolbachia-Based Approaches to Controlling Mosquito-Borne Viral Threats: Innovations, AI Integration, and Future Directions in the Context of Climate Change
Get PDFWolbachia-based mosquito control strategies have gained significant attention as a sustainable approach to reduce the transmission of vector-borne diseases such as dengue, Zika, and chikungunya. These endosymbiotic bacteria can limit the ability of mosquitoes to transmit pathogens, offering a promising alternative to traditional chemical-based interventions. With the growing impact of climate change on mosquito population dynamics and disease transmission, Wolbachia interventions represent an adaptable and resilient strategy for mitigating the public health burden of vector-borne diseases. Changes in temperature, humidity, and rainfall patterns can alter mosquito breeding habitats and extend the geographical range of disease vectors, increasing the urgency for effective control measures. This review highlights innovations in Wolbachia-based mosquito control and explores future directions in the context of climate change. It emphasizes the integration of Wolbachia with other biological approaches and the need for multidisciplinary efforts to address climate-amplified disease risks. As ecosystems shift, Wolbachia interventions could be crucial in reducing mosquito-borne diseases, especially in vulnerable regions. AI integration in Wolbachia research presents opportunities to enhance mosquito control strategies by modeling ecological data, predicting mosquito dynamics, and optimizing intervention outcomes. Key areas include refining release strategies, real-time monitoring, and scaling interventions. Future opportunities lie in advancing AI-driven approaches for integrating Wolbachia with other vector control measures, promoting adaptive, data-driven responses to climate-amplified disease transmission
Analyzing the influence of graviton fluctuations on the inflationary spectrum with a Kuchař-Torre clock
Get PDFThis paper focuses on the search for a coherent and consistent formulation to describe quantum gravity corrections to quantum field theory. We implement two fundamental ingredients discussed in previous analyses: on one hand, the construction of the Wentzel-Kramer-Brillouin and Born-Oppenheimer picture for the Wheeler-DeWitt theory of gravity and matter by using a reference fluid as physical clock; on the other hand, we explicitly separate in the metric field its own purely classical contribution from the quantum graviton degrees of freedom. This allows to derive, by the expansion in a Planckian parameter, a unitary theory properly evaluating the quantum field theory modifications in the considered regime. More specifically, we recover at zero order the standard theory on curved space-time after averaging over the graviton sector. The physical corrections are induced at first order by (quantum) gravitons, thought as the slow-varying component of the system, as opposed to the fast quantum matter and reference fluid. The genuine contribution due to gravitons, nonfactorizable into an independent phase, provides a coherent quantum gravity modification on quantum field theory. We show this by determining the predicted inflationary spectrum during an exact de Sitter phase of the primordial Universe, finding a breaking of the scale invariant morphology even when the inflation potential is modeled by a cosmological constant term. Remarkably, the behavior of such non-scale-invariant spectrum overlaps predictions previously obtained in literature by neglecting nonunitary terms emerging in those formulations. In this respect, the present model provides a satisfactory regularization of such approaches by virtue of a more realistic construction of the physical clock for the total (gravity+matter) quantum dynamics
SND@LHC: the scattering and neutrino detector at the LHC
No full textSND@LHC is a compact and stand-alone experiment designed to perform measurements with neutrinos produced at the LHC in the pseudo-rapidity region of 7.2 < η < 8.4. The experiment is located 480 m downstream of the ATLAS interaction point, in the TI18 tunnel. The detector is composed of a hybrid system based on an 830 kg target made of tungsten plates, interleaved with emulsion and electronic trackers, also acting as an electromagnetic calorimeter, and followed by a hadronic calorimeter and a muon identification system. The detector is able to distinguish interactions of all three neutrino flavours, which allows probing the physics of heavy flavour production at the LHC in the very forward region. This region is of particular interest for future circular colliders and for very high energy astrophysical neutrino experiments. The detector is also able to search for the scattering of Feebly Interacting Particles. In its first phase, the detector is ready to operate throughout LHC Run 3 and collect a total of 250 fb−1
Advanced Electrode Materials Based on Brownmillerite Calcium Ferrite for Li-Ion Batteries
Get PDFIron-based materials are considered potential anode materials for lithium-ion batteries thanks to their low cost, abundancy, non-flammability, good safety, environmental benignity, and high specific capacity. Here, a series of calcium iron oxides materials having brownmillerite structure (i. e., Ca2Fe2-xMxO5, where M=Mn, Ni and Cu and x=0 and 0.1) has been extensively studied for their use as conversion anodes in lithium cell. In particular, a mechanochemical approach has been used either to synthesize the samples and to prepare electrodes for the tests in lithium cell. Ca2Fe2O5 based electrodes proved excellent performance in lithium cell, approaching the theoretical capacity and being stable upon prolonged cycling (529 mAh g−1 at C/10 and a capacity retention of 81 % after 100 cycles). Through the use of ex-situ diffraction measurements, we have analyzed the conversion mechanism and proved the partial reversibility of its electrochemical reaction. Also, the incorporation of dopants into the structure of calcium iron oxide resulted in further improvement of its electrochemical performance as is the case of Mn doped sample that show a considerable specific capacity of 567 mAh g−1 and the capacity retention is almost 99 % after 100 cycles
Stable Deuterium-Tritium plasmas with improved confinement in the presence of energetic-ion instabilities
Get PDFProviding stable and clean energy sources is a necessity for the increasing demands of humanity. Energy produced by Deuterium (D) and Tritium (T) fusion reactions, in particular in tokamaks, is a promising path towards that goal. However, there is little experience with plasmas formed by D-T mixtures, since most of the experiments are currently performed in pure D. After more than 20 years, the Joint European Torus (JET) has carried out new D-T experiments with the aim of exploring some of the unique characteristics expected in future fusion reactors, such as the presence of highly energetic ions in low plasma rotation conditions. A new stable, high confinement and impurity-free D-T regime, with reduction of energy losses with respect to D, has been found. Multiscale physics mechanisms critically determine the thermal confinement. These crucial achievements importantly contribute to the establishment of fusion energy generation as an alternative to fossil fuels
Design of Environmental Sensor Board for Energy Harvesting: Integration of Conventional and Eco-Friendly Sensors with Power Generation Sources
Get PDFA platform for indoor monitoring inside buildings, integrating both conventional and environmentally friendly devices with energy-harvesting sources, is proposed. Biomaterials such as gelatin and chitosan, derived from renewable resources, have been utilized to fabricate hydrogel and active layers for sensors and supercapacitors. These devices enhance the environmental profile of the proposed solution by employing sustainable materials and optimizing energy consumption. The developed electronic board prototype provides a versatile platform for testing various sensor configurations while accommodating different energy-harvesting sources. The article details the design of an energy harvesting system for indoor monitoring, covering various aspects regarding energy sources, power management circuits, and low-power microcontroller units. It examines energy storage devices and sensors, including both eco-friendly and commercial ones, as well as radio transceivers with different communication technologies. Additionally, an energy analysis to evaluate the performance and energy efficiency of the platform is presented